1215 % 2 == 1 : Syntax error in expression (wrong symbol is " 1215 % 2 == 1 ")

[Maloupi]

On some books, i got this error :

((: 0
1215 % 2 == 1  : Syntax error in expression (wrong symbol is " 1215 % 2 == 1  ")

This is because ffprobe find an error in the cover file :

 libavutil      57. 17.100 / 57. 17.100
  libavcodec     59. 18.100 / 59. 18.100
  libavformat    59. 16.100 / 59. 16.100
  libavdevice    59.  4.100 / 59.  4.100
  libavfilter     8. 24.100 /  8. 24.100
  libswscale      6.  4.100 /  6.  4.100
  libswresample   4.  3.100 /  4.  3.100
  libpostproc    56.  3.100 / 56.  3.100
[mjpeg @ 0x55ed7ccd3600] EOI missing, emulating
Input #0, image2, from '/home/nausicaa/mp3/Richard Bach - Jonathan Livingston le Goéland/cover.jpg':
  Duration: 00:00:00.04, start: 0.000000, bitrate: 31782 kb/s
  Stream #0:0: Video: mjpeg (Progressive), yuvj420p(pc, bt470bg/unknown/unknown), 1215x1215 [SAR 1:1 DAR 1:1], 25 fps, 25 tbr, 25 tbn

so the regex to get the width :

ffprobe -i "/home/nausicaa/mp3/Richard Bach - Jonathan Livingston le Goéland/cover.jpg" 2>&1 | $GREP -Po "[0-9]+(?=x[0-9]+)")

give this result :

0
1215

Grep think the error code is a width.

To fix this, just say width should be at least 2 numbers :

cover_width=$(ffprobe -i "${cover_file}" 2>&1 | $GREP -Po "[0-9]{2,}+(?=x[0-9]{2,}+)")